1. Field of the Invention
The present invention relates to a method and apparatus for producing index prints, and to a density adjusting method. More particularly, the present invention relates to a method and apparatus for producing index prints wherein an index print process is performed in parallel with an ordinary print process in which images recorded on a photographic film are reproduced, by exposure, on a photosensitive material in a predetermined enlarged size, and wherein the index print process is performed such that images recorded in a plurality of frames of the photographic film are reproduced, by exposure, on the photosensitive material in a predetermined arrangement, thereby producing index prints. The present invention also relates to a method of adjusting the density of an image which is produced by surface exposure.
2. Description of the Related Art
Conventionally, prints corresponding to images in frames of a photographic film (main prints) are produced in a photographic printer. In such a photograph printer, an image recorded in each frame of a photographic film is scanned by a scanner, and the image information thus obtained (photometric data such as a cumulative transmission density) is input to a main print compensation data calculation apparatus. In this apparatus, compensation data (referred to as a main print compensation data, hereinafter) used in the exposure process are calculated based on the image information. The exposure process for the image of each frame is adjusted based on the main print compensation data.
An index print is known (see JP-A-61-122639, for example). In such an index print, images on a plurality of frames are printed in a matrix in a reduced size. This index print facilitates searching pictures recorded on a piece of developed film. In an index printer for producing index prints, image information of each frame of a photographic film captured by a scanner is received, and compensation data (referred to as an index print compensation data, hereinafter) used in the exposure process are calculated from the received image information by an index print compensation data calculation apparatus. Exposure process for the image of each frame is adjusted based on the index print compensation data.
The index print compensation data calculation apparatus and the main print compensation data calculation apparatus are separate apparatuses. Therefore, compensation data for index prints and compensation data for main prints do not coincide with each other due to mechanical errors and variations in the environment and the like. This may cause the problem that the trend of compensation for index prints does not coincide with the trend of compensation for main prints.
Meanwhile, liquid crystal display devices have conventionally been used in a TV monitor, etc. Such liquid crystal display devices are fabricated using liquid crystal panels as a main component. Liquid crystal panels are also used in photographic printers in which an image is digitally displayed on a liquid crystal panel, and light passing through the liquid crystal panel is projected onto a photosensitive material so as to print the image thereon.
Such a photographic printer is used as an index printer, as disclosed in the above described JP-A-61-122639.
The assignee of the present invention has also proposed a photographic printer in which exposure for an index print and exposure for each frame is performed successively so as to produce index prints without decreasing the high speed processing performance of the photographic printer.
The photographic printer includes a photosensitive material transport section for providing an index print area after each set of printed images is reproduced from one piece of film, and an index print section for printing images for index print (index images) in the index print area. In the index print section, a liquid crystal panel is used as a print display means.
In photographic printers of the above-described type, when an exposure process is performed by irradiating parallel light rays onto a liquid crystal panel (hereinafter referred to as "surface irradiation"), unevenness is produced in the densities of prints due to unevenness in the intensity of the light rays from a light source. An ideal print with no unevenness in its density is shown on the left side in FIG. 9A, while a print with unevenness in its density is shown in on the right side in FIG. 9A. In these photographic printers, an optical device such as a diffusing plate is provided to eliminate unevenness in the intensity of light rays, thereby preventing unevenness in the densities of prints.
However, when such an optical device is built into a photographic printer, the number of components increases, and the size of the photographic printer increases. Also, optical adjustments such as adjustment of the focal distance must be performed after the optical device is built into the photographic printer during its manufacturing stage, and after the optical device is exchanged.